1. Field of the Invention
The invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine.
2. Description of the Prior Art
From German Patent Disclosure DE 10 2006 008 648 A1, a fuel injector embodied as a common rail injector is known that has a two-part injection valve element, which is triggerable via a control valve (servo valve). The two parts of the injection valve element are coupled to one another via a hydraulic coupler. In the state of repose of the fuel injector, rail pressure prevails in the hydraulic coupler. The known fuel injector has little leakage; that is, it is embodied with a low-pressure stage. To attain an adequate hydraulic needle closing force, a closing throttle restriction is placed in a connecting conduit that supplies a lower nozzle chamber with fuel. One disadvantage of the known fuel injector is that upon triggering of the injection valve element, the two parts of the injection valve element do not react like a single part but instead react with a delay. This can be compensated for only by very fast-switching control valves, but they entail higher costs.